With the digitization of various medical information as well as the wide use of world wide web and its related technologies, research has quickened its pace in utilizing high speed information networks to build wide area Electronic Patient Record system EPR for short) after having progressively perfected the construction of hospital information digitization. It is achieved mainly by connecting a patient's information stored in various hospitals through a high speed network (Internet or private network), making it easy to mutually transfer the patient's health record, including diagnostic reports, clinical records, radiological images, laboratory testing information and so on, according to the patient's medical conditions and needs, in the network among hospital's various internal departments, various hospital information systems as well as various hospitals. There is a need for hospitals' various medical information systems (PACS, RIS, HIS, EPR etc.,) be integrated and that seamless flow of multimedia data be realized between the information systems, so that a clinician may effectively use medical information, improve clinical diagnosis, the level of treatment, healthcare service, service quality and efficiency, and meanwhile, greatly save on resources.
The main bottleneck in integrating various kinds of hospital imaging information systems such as cross-vendors PACSs to achieve seamless medical data flow between them is: various systems are developed by different companies while radiological medical images are mostly high definition (≧2K×2K, such as CR, DR, Mammography etc), big file sizes (60-400 Megabytes, such as MR, CT, US Series etc.), and appear in various network archiving situations, various media forms (static images, dynamic images, two-dimensional or three-dimensional and so on). Under the precondition of ensuring medical diagnosis quality, it is very difficult to perfectly realize safe, reliable, efficient and high speed data archiving and retrieval. Although there were some systematic solutions before this, there is still not one system able to integrate the distributed, differently structured archived resources including DICOM images, non-DICOM images, text, audio and such multimedia resources and centering around the patient, centrally manage the resources in a virtual way and safely and reliably operate without interruption.